<!doctype html> 
<html style='font-size:1px;'> 
<head> 
    <meta charset="utf-8"> 
    <title></title>
    <style type="text/css">
*{margin: 0;padding: 0;list-style: none;}
html,body{
	height: 100%;
}
div{
	width: 5rem;height: 5rem;background: black;
}


    </style> 


</head>
<body>
	<script type="text/javascript">
	/*16*20=320
      10*32=320
      32*10=320
      320 1 = 320

      400px = 20rem
      320/32 = 10

	*/
	/*
	document.documentElement.style.fontSize = innerWidth/16+'px';
	onresize = function(){
		document.documentElement.style.fontSize = innerWidth/16+'px';
	};
	*/

	</script>
	<div></div>
</body>
</html>